Page 168 - 《振动工程学报》2025年第9期
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第 38 卷第 9 期                       振 动 工 程 学 报                                       Vol. 38 No. 9
               2025 年  9 月                     Journal of Vibration Engineering                       Sept. 2025



                        悬   臂   式   转    子   -轴   承   系    统   热   弯   曲   振    动   特   性   分    析



                                   宋华庆 , 董兴建 , 陈康康 , 杨昔科 , 张 燕                           2
                                                                  1
                                            1
                                                       1
                                                                             2
                    (1. 上海交通大学振动、冲击、噪声研究所,上海 200240; 2. 上海电气电站设备有限公司发电机厂,上海 200240)
              摘要:滑动轴承的楔形油膜对于高速旋转的转子轴颈有不均匀加热效应,使得轴颈产生周向温差。周向温差所导致的热弯曲
              会加剧转子振动,甚至造成转子热失稳,即所谓“莫顿效应”。对于悬臂式转子,莫顿效应尤其严重。本文建立椭圆轴承的热
              流体润滑模型并计算其动力系数及油膜温度场,基于傅里叶热传导理论,以所得油膜温度为边界条件,采用有限元方法求解
              轴颈三维瞬态温度场以获得轴颈热变形与热应力,对过热应力积分获得等效弯矩,并将其应用于转子动力学分析,同时基于
              热变形更新滑动轴承油膜厚度。重复上述步骤便完成了转子-轴承系统的流-固-热多场耦合分析,基于试验数据验证仿真模
              型的有效性。以转子悬臂长度及悬垂质量为参数,对转子-轴承系统进行参数分析。结果表明,缩短悬臂长度或减小悬垂质量
              可有效降低系统振动。

              关键词: 滑动轴承;莫顿效应;转子动力学;热弯曲;热稳定性
              中图分类号:TH113        文献标志码:A        DOI:10.16385/j.cnki.issn.1004-4523.202309026



                                 Vibration characteristics analysis of thermal bending
                                           for cantilever rotor-bearing system

                                                                       1
                                                                                   2
                                         1
                                                        1
                             SONG Huaqing ,DONG Xingjian ,CHEN Kangkang ,YANG Xike ,ZHANG Yan  2
                          (1.Institute of Vibration,Shock and Noise,Shanghai Jiao Tong University,Shanghai 200240,China;
                          2.Shanghai Electric Power Generation Equipment Co.,Ltd.,Generator Plant,Shanghai 200240,China)
              Abstract:The wedge-shaped oil film in sliding bearings induces uneven heating effects on the journal of a rapidly rotating rotor,resulting in
              circumferential temperature variations in the journal. The thermal bending caused by these temperature differences exacerbates rotor vibration,
              leading  to  a  phenomenon  known  as  ‘Morton  effect’  or  rotor  thermal  instability.  This  effect  is  particularly  severe  in  cantilevered  rotors.
              Initially,an elliptical bearing’s thermal fluid lubrication model is established,and its dynamic coefficients and oil film temperature field are
              calculated. Subsequently,based on Fourier heat conduction theory,using the obtained oil film temperature as a boundary condition,a finite
              element method is employed to solve the three-dimensional transient temperature field of the journal to determine the thermal deformation and
              thermal  stress.  The  thermal  stress  is  then  integrated  to  obtain  an  equivalent  moment  for  rotor  dynamic  analysis.  Additionally, the  sliding
              bearing oil film thickness is updated based on thermal deformation. Repeating these steps completes the fluid-solid-thermal multi-field coupling
              analysis of the rotor-bearing system,and the effectiveness of the simulation model is validated against experimental data. Finally,parameter
              analysis is conducted on the rotor-bearing system with the rotor’s cantilever length and suspended mass as variables. The results indicate that
              reducing the cantilever length or decreasing the suspended mass effectively reduces system vibration.

              Keywords:plain bearing;Morton effect;rotor dynamics;thermal bending;thermal stability

                  转子-轴承系统广泛应用于电力机械、船舶重                          程设备中,由于结构、空间等条件的限制,部分转子
              工、石油开采等重工业领域 。转子-轴承系统在工                           带有较长的外伸段,形成悬臂式转子结构 。由于悬
                                                                                                     [3]
                                       [1]
              作状态下,轴颈与轴瓦表面之间的楔形润滑油膜在                            臂式转子具有较大的外伸质量,因此受到热弯曲的
              避免转子与轴承直接接触带来磨损的同时,其内部                            影响更为显著,相较于非悬臂式转子来说,悬臂式转
              发生不均匀黏性剪切,产生不均匀油膜温度场,并对                           子更容易发生莫顿效应。
              转子轴颈产生不均匀加热,使得轴颈出现周向温差                                莫顿效应涉及流-热-固多物理场耦合,传统的转
              进而导致转子发生热弯曲,加剧转子振动,甚至导致                           子动力学方法无法对其进行准确建模;同时由于热
              转子失稳,这种现象被称之为“莫顿效应” 。在工                           弯曲引起的热不平衡具有幅值与相位不断变化的特
                                                    [2]


                  收稿日期:2023-09-10;修订日期:2023-12-25
                  基金项目:国家自然科学基金资助项目             (12272219)
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